There is a need for High Definition Television (HDTV) output signals from DVD players and other such video source devices. However, the Hollywood movie industry wants to provide copy protection on these High Definition (HD) output signals that performs the same function as the known Macrovision Corp. Anti-copy Process (ACP) present on the NTSC or PAL television output signal of virtually every DVD player now in existence. One version of the Macrovision ACP is described in U.S. Pat. No. 4,631,603.
The technical problem is conveying HDTV analog signals from a DVD player or set-top cable TV decoder box to a TV set. If the video is in the clear, it is subject to being copied by HDTV video recorders, or to being converted to NTSC or PAL TV and then being copied on conventional VHS and 8 mm video recorders. Watermarking—with appropriate detection circuitry in future compliant recorders—has the potential to solve this recording problem to the extent that it provides a means to convey copy control information, (although it will not help with the NTSC/PAL converter problem). However, a viable watermarking technology has yet to be defined and adopted. In addition, watermarking does not address potential recording devices which are not compliant with the watermarking system; whereas, this disclosure addresses those non-compliant recording devices.